Lifting devices or jacks for handling heavy equipment are well known. Such devices find particular application in the automotive or truck maintenance industry where it is often necessary to install or remove heavy components such as planetary devices, clutch assemblies, brakesavers, flywheels or flywheel housings.
Various prior art heavy component handling devices are known to applicant. U.S. Pat. No. 2,814,099 to Knittel discloses an adjustable stand and cradle for handling transmissions. U.S. Pat. No. 1,909,023 to Statz discloses a transmission jack which is compact in design so as to occupy a minimum of space beneath a vehicle. U.S. Pat. No. 2,702,689 to Smith discloses a vehicle dolly arrangement to support a differential unit. U.S. Pat. No. 3,109,626 to Arnes et al. discloses a jack for servicing transmissions, differentials and similar units of various types.
Despite the presence of the prior art devices, it is still common in the industry to manually install heavy components. For example, flywheel assemblies that weigh approximately 150 pounds are often installed by a mechanic lying on his back under a truck with the assembly resting on his chest. He then manually lifts the assembly up to the housing where a second mechanic pushes the assembly horizontally into the housing. Unfortunately this procedure often results in back and hand/finger injuries. If the assembly falls, stomach and chest injuries are possible.